The synthesis of polytriphenylamine networks (PTPAs) was accomplished by FeCl3-promoted one-step oxidative coupling reaction and Friedel–Crafts alkylation in one pot. For the first time, we used the common reagents including trimethyl orthoformate (TMOF), trimethyl orthoacetate (TMOA), triethyl orthoacetate (TEOA) and triisopropyl orthoformate (TIPO) as the crosslinkers, respectively. The highest BET specific surface area is 1543 m2 g−1, for PTPA-4. Its CO2 uptake capacity is as high as 2.65 mmol g−1 at 1.0 bar and 273 K, which makes it promising candidate for applications in environment fields. In addition, this work extends the types of cheap crosslinkers that could be incorporated into porous organic polymers to enhance their porosity.